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To: Magnus Hagander <magnus@hagander.net>
cc: Andrew Dunstan <andrew@dunslane.net>, Bruce Momjian <bruce@momjian.us>,
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Subject: Re: [HACKERS] Moving tablespaces 
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Comments: In-reply-to Magnus Hagander <magnus@hagander.net>
	message dated "Tue, 06 Dec 2011 15:59:11 +0100"
Date: Tue, 06 Dec 2011 10:12:32 -0500
Message-ID: <19894.1323184352@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Magnus Hagander <magnus@hagander.net> writes:
> AFAICT, it should be as simple as the attached.

Oh, one other thought is that the function body has to be
conditionalized on HAVE_READLINK (the fact that you forgot that
somewhere else isn't an excuse for not doing it here).  IIRC,
only the two built-in tablespaces can exist when not HAVE_READLINK,
so it seems sufficient to handle those cases and then PG_RETURN_NULL
(or maybe throw error) when not HAVE_READLINK.

			regards, tom lane